1. Technical Field
The present invention relates to a gyro sensor and an electronic device using the gyro sensor.
2. Related Art
Recently, many gyro sensors which detect angular velocity have been used for car navigation systems, or attitude control such as hand-shake correction of video cameras. Examples of such gyro sensors include a sensor in which detection elements capable of detecting the angular velocities about the X-axis, the Y-axis, and the Z-axis perpendicular to each other are provided for the respective axes.
A gyro sensor disclosed in JP-A-2010-266321 is a multi-axis angular velocity sensor which detects the angular velocities about first to third detection axes perpendicular to each other. The gyro sensor includes a first vibration-type angular velocity sensor element which detects the angular velocity about the first detection axis, a second vibration-type angular velocity sensor element which detects the angular velocity about the second detection axis, a third vibration-type angular velocity sensor element which detects the angular velocity about the third detection axis, an IC which controls the first to third vibration-type angular velocity sensor elements, and a package which contains the first to third vibration-type angular velocity sensor elements and the IC. In the gyro sensor, the vibration plane of the first vibration-type angular velocity sensor element is parallel to a first detection axis, the vibration plane of the second vibration-type angular velocity sensor element is parallel to a second detection axis, and the vibration plane of the third vibration-type angular velocity sensor element is perpendicular to a third detection axis, so that the gyro sensor is reduced in height.
However, gyro sensors in the related art have a problem that when respective axes are arranged in a chip for detecting the angular velocities about the three axes, the mounting area is increased, failing to achieve further miniaturization of a sensor element associated with the request for miniaturization of the entire device.
Moreover, since vibrations are independent in each of single-axis angular velocity sensors, a drive circuit has also to be disposed in each of the angular velocity sensors. Therefore, an integrated circuit (IC) is also needed separately, and the mounting area is increased, making it difficult to miniaturize the sensor. Moreover, since a vibration mode exists in each of the plurality of angular velocity sensors, there is a problem that the vibration modes interfere with each other.